1. Field of the Invention
The present invention relates to a chassis of a walk-substituting cart, more particularly one, which includes front and rear chassis, and is easy and rapid to assemble, and whose terminals will automatically come into contact in order to electrically connect the power supply unit to the actuating motor as soon as the front and the rear chassis are coupled.
2. Brief Description of the Prior Art
Referring to FIGS. 9 and 10, U.S. Pat. No. 6,439,331 teaches a “CHASSIS OF AN ELECTRIC WALK-SUBSTITUTING CAR”, which was invented by the inventor of the present invention, and whose filing date and application number are Aug. 21, 2000, and Ser. No. 09/641,938 respectively. The chassis of an electric walk-substituting car includes a front chassis 91, a middle chassis 92, and a rear chassis 93 joined together. The front chassis 91 has a vertical connect rod 911 provided at a rear side and a fix rod 912 fixed laterally under the lower end of the vertical connect rod 911, which has two ends respectively connected to a support rod 913 extending lengthwise forward. Further, the connect rod 911 has an inverted U-shape combine plate 914 fixed on its upper rear side, and a chair is combined on the upper end of the connect rod 911. The inverted U-shape combine plate 914 has opposed connecting holes 9141 on two lateral sides thereof.
The middle chassis 92 has a vertical combine rod 921 and a lateral rod 922 located under the combine rod 921. The lateral rod 922 has an L-shaped plate 923 respectively at two sides in front of the lateral rod 922. Each L-shaped plate 923 has a vertical portion 9231 defining an insert aperture 924 with the lateral rod 922 for the fix rod 912 of the front chassis 91 to fit therein. A pivot connector 925 is respectively fixed at two sides of the rear wall of the lateral rod 922. A lateral elongate strip 926 is provided at the rear side of the middle chassis 92, and a combine means 927 respectively fixed at two ends of the strip 926. The vertical combine rod 921 has a through hole 9211 at an upper end thereof.
The rear chassis 93 has a side rod 931 respectively extending lengthwise parallel at two sides, and each side rod 931 has a pivot hole 932 formed in a front side to be pivotally connected to each pivot connector 925 of the middle chassis 92, a connect means 933 respectively fixed on an outer side of each side rod 931 and aligned to each other to be connected to each combine means 927 of the middle chassis 92 with a bolt and nut 934 fitted around by a coil spring 935.
A power-supply unit is positioned on a rear end of the front chassis 91, and connected to cords 94 having a connecting element 941 connected thereto. And, an actuating motor is positioned on the rear chassis 93, and connected to cords 95 having a connecting element 951 connected thereto; thus, the power-supply unit can be electrically connected to the actuating motor by means of connecting the connecting elements 941 and 951.
In assembling, firstly, the fix rod 912 of the front chassis 91 is inserted in the inert aperture 924 of the middle chassis 92, then the upper end of the combine rod 921 is inserted in the combine plate 914 on the upper end of the connect rod 911. And, a screw button 915 is passed through the holes 9141 of the combine plate 914 and the through holes 9211 of the combine rod 921 to join the front chassis 5 and the middle chassis 6. Next, the pivot holes 932 of the two side rods 931 of the rear chassis 93 are fitted in the two pivot connectors 925 and two pivots are respectably inserted through the pivot holes 932 and the pivot connectors 925 so that the two side rods 931 and the rod 922 are pivotally connected to each other. Lastly, insert the bolts 934 through the combine means 927 and the two connect means 933 of the side rods 931 of the rear chassis 93 and screw the bolts 934 with the nuts, with two coil springs 935 respectively fitted around the two bolts 934, which coil springs 935 will produce elasticity to absorb vibration as to make the car comfortable to ride on.
The above electric walk-substituting car is found to have the following disadvantages:
1. It takes relatively much time to join the front and the middle chassis because the user has to take the trouble to pass a threaded fixing element through the holes of both the inverted U-shape combine plate and the vertical combine rod in order to secure the front chassis to the middle one after the front and the middle chassis are positioned together with the vertical connect rod abutting the vertical combine rod.
2. After the chassis is assembled, the user has to take the trouble to connect the connecting elements of the power-supply unit to those of the actuating motor in order to electrically connect the power-supply unit to the actuating motor. Therefore, the chassis isn't convenient to use.